[PATCH 57/67] aufs sysfs interface
From: hooanon05
Date: Fri May 16 2008 - 10:45:51 EST
From: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
initial commit
aufs sysfs interface
Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
---
fs/aufs/sysfs.c | 459 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 459 insertions(+), 0 deletions(-)
diff --git a/fs/aufs/sysfs.c b/fs/aufs/sysfs.c
new file mode 100644
index 0000000..eb0d367
--- /dev/null
+++ b/fs/aufs/sysfs.c
@@ -0,0 +1,459 @@
+/*
+ * Copyright (C) 2007-2008 Junjiro Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * sysfs interface
+ *
+ * $Id: sysfs.c,v 1.3 2008/05/12 00:27:58 sfjro Exp $
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/sysfs.h>
+#include "aufs.h"
+
+
+#ifdef CONFIG_AUFS_LOCAL
+static ssize_t config_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+#define conf_bool(name) "CONFIG_AUFS_" #name "=y\n"
+ static const char opt[] =
+#ifdef CONFIG_AUFS
+ "CONFIG_AUFS=y\n"
+#else
+ "CONFIG_AUFS=m\n"
+#endif
+#ifdef CONFIG_AUFS_FAKE_DM
+ conf_bool(FAKE_DM)
+#endif
+#ifdef CONFIG_AUFS_BRANCH_MAX_127
+ conf_bool(BRANCH_MAX_127)
+#elif defined(CONFIG_AUFS_BRANCH_MAX_511)
+ conf_bool(BRANCH_MAX_511)
+#elif defined(CONFIG_AUFS_BRANCH_MAX_1023)
+ conf_bool(BRANCH_MAX_1023)
+#elif defined(CONFIG_AUFS_BRANCH_MAX_32767)
+ conf_bool(BRANCH_MAX_32767)
+#endif
+#ifdef CONFIG_AUFS_HINOTIFY
+ conf_bool(HINOTIFY)
+#endif
+#ifdef CONFIG_AUFS_EXPORT
+ conf_bool(EXPORT)
+#endif
+#ifdef CONFIG_AUFS_ROBR
+ conf_bool(ROBR)
+#endif
+#ifdef CONFIG_AUFS_SHWH
+ conf_bool(SHWH)
+#endif
+#ifdef CONFIG_AUFS_DLGT
+ conf_bool(DLGT)
+#endif
+#ifdef CONFIG_AUFS_RR_SQUASHFS
+ conf_bool(RR_SQUASHFS)
+#endif
+#ifdef CONFIG_AUFS_SEC_PERM_PATCH
+ conf_bool(SEC_PERM_PATCH)
+#endif
+#ifdef CONFIG_AUFS_SPLICE_PATCH
+ conf_bool(SPLICE_PATCH)
+#endif
+#ifdef CONFIG_AUFS_PUT_FILP_PATCH
+ conf_bool(PUT_FILP_PATCH)
+#endif
+#ifdef CONFIG_AUFS_LHASH_PATCH
+ conf_bool(LHASH_PATCH)
+#endif
+#ifdef CONFIG_AUFS_FSYNC_SUPER_PATCH
+ conf_bool(FSYNC_SUPER_PATCH)
+#endif
+#ifdef CONFIG_AUFS_DENY_WRITE_ACCESS_PATCH
+ conf_bool(DENY_WRITE_ACCESS_PATCH)
+#endif
+#ifdef CONFIG_AUFS_KSIZE_PATCH
+ conf_bool(KSIZE_PATCH)
+#endif
+#ifdef CONFIG_AUFS_WORKAROUND_FUSE
+ conf_bool(WORKAROUND_FUSE)
+#endif
+#ifdef CONFIG_AUFS_STAT
+ conf_bool(STAT)
+#endif
+#ifdef CONFIG_AUFS_DEBUG
+ conf_bool(DEBUG)
+#endif
+#ifdef CONFIG_AUFS_COMPAT
+ conf_bool(COMPAT)
+#endif
+
+/* automatic configurations */
+#ifdef CONFIG_AUFS_BR_NFS
+ conf_bool(BR_NFS)
+#endif
+#ifdef CONFIG_AUFS_MAGIC_SYSRQ
+ conf_bool(MAGIC_SYSRQ)
+#endif
+ ;
+#undef conf_bool
+
+ char *p = buf;
+ const char *end = buf + PAGE_SIZE;
+
+ p += snprintf(p, end - p, "%s", opt);
+#ifdef DbgUdbaRace
+ if (p < end)
+ p += snprintf(p, end - p, "DbgUdbaRace=%d\n", DbgUdbaRace);
+#endif
+ if (p < end)
+ return p - buf;
+ else
+ return -EFBIG;
+}
+
+static struct kobj_attribute au_config_attr = __ATTR_RO(config);
+#endif
+
+#ifdef CONFIG_AUFS_STAT
+static ssize_t stat_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ char *p = buf;
+ const char *end = buf + PAGE_SIZE;
+ int i;
+
+ p += snprintf(p, end - p, "wkq max_busy:");
+ for (i = 0; p < end && i < aufs_nwkq; i++)
+ p += snprintf(p, end - p, " %u", au_wkq[i].max_busy);
+ if (p < end)
+ p += snprintf(p, end - p, ", %u(generic)\n",
+ au_wkq[aufs_nwkq].max_busy);
+
+ if (p < end)
+ return p - buf;
+ else
+ return -EFBIG;
+}
+
+static struct kobj_attribute au_stat_attr = __ATTR_RO(stat);
+#endif
+
+#ifdef CONFIG_AUFS_DEBUG
+static ssize_t debug_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%d\n", au_debug_test());
+}
+
+static ssize_t debug_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t sz)
+{
+ LKTRTrace("%.*s\n", (unsigned int)sz, buf);
+
+ if (unlikely(!sz || (*buf != '0' && *buf != '1')))
+ return -EOPNOTSUPP;
+
+ if (*buf == '0')
+ au_debug_off();
+ else if (*buf == '1')
+ au_debug_on();
+ return sz;
+}
+
+static struct kobj_attribute au_debug_attr = __ATTR(debug, S_IRUGO | S_IWUSR,
+ debug_show, debug_store);
+#endif
+
+static struct attribute *au_attr[] = {
+#ifdef CONFIG_AUFS_LOCAL
+ &au_config_attr.attr,
+#endif
+#ifdef CONFIG_AUFS_STAT
+ &au_stat_attr.attr,
+#endif
+#ifdef CONFIG_AUFS_DEBUG
+ &au_debug_attr.attr,
+#endif
+ NULL, /* need to NULL terminate the list of attributes */
+};
+
+static struct attribute_group au_attr_group_body = {
+ .attrs = au_attr
+};
+
+struct attribute_group *au_attr_group = &au_attr_group_body;
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * they are copied from linux/lib/kobject.c,
+ * and will be exported in the future.
+ */
+static ssize_t au_attr_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct kobj_attribute *kattr;
+ ssize_t ret = -EIO;
+
+ kattr = container_of(attr, struct kobj_attribute, attr);
+ if (kattr->show)
+ ret = kattr->show(kobj, kattr, buf);
+ return ret;
+}
+
+#ifdef CONFIG_AUFS_DEBUG
+static ssize_t au_attr_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct kobj_attribute *kattr;
+ ssize_t ret = -EIO;
+
+ kattr = container_of(attr, struct kobj_attribute, attr);
+ if (kattr->store)
+ ret = kattr->store(kobj, kattr, buf, count);
+ return ret;
+}
+#endif
+
+static struct sysfs_ops sysaufs_ops = {
+ .show = au_attr_show,
+#ifdef CONFIG_AUFS_DEBUG
+ .store = au_attr_store
+#endif
+};
+
+static struct kobj_type au_ktype_body = {
+ .sysfs_ops = &sysaufs_ops
+};
+struct kobj_type *au_ktype = &au_ktype_body;
+
+/* ---------------------------------------------------------------------- */
+
+int sysaufs_sbi_xino(struct seq_file *seq, struct super_block *sb)
+{
+ int err, dlgt;
+ struct au_sbinfo *sbinfo;
+ unsigned int mnt_flags;
+ aufs_bindex_t bend, bindex;
+ struct file *xf;
+ struct kstat st;
+
+ AuTraceEnter();
+
+ sbinfo = au_sbi(sb);
+ mnt_flags = au_mntflags(sb);
+ if (unlikely(!au_opt_test(mnt_flags, XINO))) {
+#ifdef CONFIG_AUFS_DEBUG
+ AuDebugOn(sbinfo->si_xib);
+ bend = au_sbend(sb);
+ for (bindex = 0; bindex <= bend; bindex++)
+ AuDebugOn(au_sbr(sb, bindex)->br_xino);
+#endif
+ err = 0;
+ goto out; /* success */
+ }
+
+ dlgt = !!au_opt_test_dlgt(mnt_flags);
+ xf = sbinfo->si_xib;
+ err = vfsub_getattr(xf->f_vfsmnt, xf->f_dentry, &st, dlgt);
+ if (!err)
+ seq_printf(seq, "%Lux%lu %Ld\n",
+ st.blocks, st.blksize, (long long)st.size);
+ else
+ seq_printf(seq, "err %d\n", err);
+
+ bend = au_sbend(sb);
+ for (bindex = 0; !err && bindex <= bend; bindex++) {
+ xf = au_sbr(sb, bindex)->br_xino;
+ if (!xf)
+ continue;
+ seq_printf(seq, "%d: ", bindex);
+ err = vfsub_getattr(xf->f_vfsmnt, xf->f_dentry, &st, dlgt);
+ if (!err)
+ seq_printf(seq, "%d, %Lux%lu %Ld\n",
+ file_count(xf), st.blocks, st.blksize,
+ (long long)st.size);
+ else
+ seq_printf(seq, "err %d\n", err);
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/*
+ * the lifetime of branch is independent from the entry under sysfs.
+ * sysfs handles the lifetime of the entry, and never call ->show() after it is
+ * unlinked.
+ */
+#define SysaufsBr_PREFIX "br"
+static int sysaufs_sbi_br(struct seq_file *seq, struct super_block *sb,
+ aufs_bindex_t bindex)
+{
+ int err;
+ struct dentry *root;
+ struct au_branch *br;
+ struct path path;
+
+ LKTRTrace("b%d\n", bindex);
+
+ err = -ENOENT;
+ if (unlikely(au_sbend(sb) < bindex))
+ goto out;
+
+ err = 0;
+ root = sb->s_root;
+ di_read_lock_parent(root, !AuLock_IR);
+ br = au_sbr(sb, bindex);
+ path.mnt = br->br_mnt;
+ path.dentry = au_h_dptr(root, bindex);
+ seq_path(seq, &path, au_esc_chars);
+ di_read_unlock(root, !AuLock_IR);
+ seq_printf(seq, "=%s\n", au_optstr_br_perm(br->br_perm));
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static struct seq_file *au_seq(char *p, ssize_t len)
+{
+ struct seq_file *seq;
+
+ seq = kzalloc(sizeof(*seq), GFP_TEMPORARY);
+ if (seq) {
+ //mutex_init(&seq.lock);
+ seq->buf = p;
+ seq->count = 0;
+ seq->size = len;
+ return seq; /* success */
+ }
+
+ seq = ERR_PTR(-ENOMEM);
+ AuTraceErrPtr(seq);
+ return seq;
+}
+
+//todo: file size may exceed PAGE_SIZE
+ssize_t sysaufs_sbi_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ ssize_t err;
+ struct au_sbinfo *sbinfo;
+ struct super_block *sb;
+ struct seq_file *seq;
+ char *name;
+ struct attribute **cattr;
+
+ LKTRTrace("%s/%s\n", kobject_name(kobj), attr->name);
+
+ sbinfo = container_of(kobj, struct au_sbinfo, si_kobj);
+ sb = sbinfo->si_sb;
+ si_noflush_read_lock(sb);
+
+ seq = au_seq(buf, PAGE_SIZE);
+ err = PTR_ERR(seq);
+ if (IS_ERR(seq))
+ goto out;
+
+ name = (void *)attr->name;
+ cattr = au_sbi_attrs;
+ while (*cattr) {
+ if (!strcmp(name, (*cattr)->name)) {
+ err = container_of(*cattr, struct au_sbi_attr, attr)
+ ->show(seq, sb);
+ goto out_seq;
+ }
+ cattr++;
+ }
+
+ if (!strncmp(name, SysaufsBr_PREFIX, sizeof(SysaufsBr_PREFIX) - 1)) {
+ name += sizeof(SysaufsBr_PREFIX) - 1;
+ err = sysaufs_sbi_br(seq, sb, simple_strtol(name, NULL, 10));
+ goto out_seq;
+ }
+ BUG();
+
+ out_seq:
+ if (!err) {
+ err = seq->count;
+ /* sysfs limit */
+ if (unlikely(err == PAGE_SIZE))
+ err = -EFBIG;
+ }
+ kfree(seq);
+ out:
+ si_read_unlock(sb);
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+void sysaufs_br_init(struct au_branch *br)
+{
+ br->br_attr.name = br->br_name;
+ br->br_attr.mode = S_IRUGO;
+ br->br_attr.owner = THIS_MODULE;
+}
+
+void sysaufs_brs_del(struct super_block *sb, aufs_bindex_t bindex)
+{
+ struct au_sbinfo *sbinfo;
+ aufs_bindex_t bend;
+
+ LKTRTrace("b%d\n", bindex);
+
+ if (!sysaufs_brs)
+ return;
+
+ sbinfo = au_sbi(sb);
+ bend = au_sbend(sb);
+ for (; bindex <= bend; bindex++)
+ sysfs_remove_file(&sbinfo->si_kobj,
+ &au_sbr(sb, bindex)->br_attr);
+}
+
+void sysaufs_brs_add(struct super_block *sb, aufs_bindex_t bindex)
+{
+ int err;
+ struct kobject *kobj;
+ aufs_bindex_t bend;
+ struct au_branch *br;
+
+ LKTRTrace("b%d\n", bindex);
+
+ if (!sysaufs_brs)
+ return;
+
+ kobj = &au_sbi(sb)->si_kobj;
+ bend = au_sbend(sb);
+ for (; bindex <= bend; bindex++) {
+ br = au_sbr(sb, bindex);
+ snprintf(br->br_name, sizeof(br->br_name),
+ SysaufsBr_PREFIX "%d", bindex);
+ err = sysfs_create_file(kobj, &br->br_attr);
+ if (unlikely(err))
+ AuWarn("failed %s under sysfs(%d)\n", br->br_name, err);
+ }
+}
--
1.4.4.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/